TOXICOLOGICAL PROFILE FOR CHROMIUM - Davidborowski.com

CHROMIUM 2162. HEALTH EFFECTSchromium acetate monohydrate. Similarly chromium levels were significantly elevated in the offspringof rats administered chromium in the form of GTF from Brewer’s yeast by gavage than in the offspring ofrats administered chromium trichloride intravenously or by gavage.There is very little information available in which to assess whether the pharmacokinetic properties ofchromium would be different in children. Sullivan et al. (1984) found that gastrointestinal absorption ofradiolabelled chromium chloride, administered by gavage, was 10 times higher in 2-day-old rats ascompared to levels absorbed in adult rats. A similar pattern of distribution in the body was found in theimmature and mature rats.2.8 BIOMARKERS OF EXPOSURE AND EFFECTBiomarkers are broadly defined as indicators signaling events in biologic systems or samples. They havebeen classified as markers of exposure, markers of effect, and markers of susceptibility (NAS/NRC 1989).Due to a nascent understanding of the use and interpretation of biomarkers, implementation of biomarkersas tools of exposure in the general population is very limited. A biomarker of exposure is a xenobioticsubstance or its metabolite(s) or the product of an interaction between a xenobiotic agent and some targetmolecule(s) or cell(s) that is measured within a compartment of an organism (NAS/NRC 1989). Thepreferred biomarkers of exposure are generally the substance itself or substance-specific metabolites inreadily obtainable body fluid(s), or excreta. However, several factors can confound the use andinterpretation of biomarkers of exposure. The body burden of a substance may be the result of exposuresfrom more than one source. The substance being measured may be a metabolite of another xenobioticsubstance (e.g., high urinary levels of phenol can result from exposure to several different aromaticcompounds). Depending on the properties of the substance (e.g., biologic half-life) and environmentalconditions (e.g., duration and route of exposure), the substance and all of its metabolites may have left thebody by the time samples can be taken. It may be difficult to identify individuals exposed to hazardoussubstances that are commonly found in body tissues and fluids (e.g., essential mineral nutrients such ascopper, zinc, and selenium). Biomarkers of exposure to chromium are discussed in Section 2.8.1.Biomarkers of effect are defined as any measurable biochemical, physiologic, or other alteration within anorganism that, depending on magnitude, can be recognized as an established or potential healthimpairment or disease (NAS/NRC 1989). This definition encompasses biochemical or cellular signals oftissue dysfunction (e.g., increased liver enzyme activity or pathologic changes in female genital epithelial